This invention relates to beverage dispensing apparatus of the type in which several different carbonated beverages are dispensed from a single beverage dispensing head by mixing soda and syrup at the head, the soda and syrup supplied to the head through a number of hoses from a pressurized beverage component source.
Hand held beverage dispensers which provide the operator with the ability to dispense a number of different carbonated beverages by merely pressing an appropriate button have become quite popular. An example of such a beverage dispensing apparatus is shown in U.S. Pat. No. 3,863,810 to Hanson. This patent discloses the use of dual-valve valve stems connected to each button. One of the valve elements on each of the valve stems controls fluid flow through a soda channel and the other valve element controls the flow of fluid through a syrup channel. Therefore, each button operates two valves to control the passage of syrup and soda from the pressurized beverage component source to the nozzle. To accommodate the two valves, four O-rings are required for each valve stem. Because of the numerous syrup and soda passageways required, the number of beverages accommodated in a chosen size dispensing head is limited. Also, since the four O-rings must be properly aligned, relatively tight manufacturing tolerances are necessary. Further, replacement of a worn or broken O-ring can be quite a problem with a dispensing head similar to that shown in Hanson.
The amount of beverage dispensed by one type of conventional beverage dispensers is determined by how long the button is depressed. Other conventional beverage dispensers are programmed to meter correct amounts of a beverage automatically. Regardless of how the amount is controlled, the proportion of soda to syrup must be controlled for each beverage. This is commonly done through the use of one or more brixing devices. Brixing devices typically use a valve, similar to a gate valve, in which two intersecting cylinders are used to control the flow through the valve. Since this type of valve lacks the ability to provide a positive shut off, depending upon the tightness of fit the brixing valve may allow syrup or soda to slowly leak past the brixing device and out the head.